The present disclosure relates to a vehicle control device, and particularly to an art for vibration damping control during vehicle acceleration.
Conventionally, it is known that vibration occurs in vehicles due to torsion in a driving force transmission shaft provided between a drive source (such as an engine) and vehicle wheels. In order to reduce such vibration, various research and development has been conducted.
For example, JP3750626B discloses an art for estimating, by using an observer (state estimator), a torsion angle of a torsional damper that is provided between an engine and a motor of a hybrid electric vehicle, and correcting a crank angle of the engine based on the estimated torsion angle. Thus, torsional vibration of a driving force transmission shaft is reduced.
Further, JP5920147B discloses an art for reducing vehicle vibration caused by torsion in a driving force transmission shaft during a gear shift, i.e., when a gear reduction ratio of a transmission is changed. For example, rotational speeds of a drive shaft at an engine side and a vehicle wheel side are estimated by using an observer model, a difference between the estimated speeds is calculated, and a feedback control is executed by using a torque correction amount based on the calculated speed difference. Thus, the vehicle vibration caused by torsion in the driving force transmission shaft during the gear shift is reduced.
With the conventional arts, a satisfactory acceleration sensation, when a vehicle driver depresses an accelerator pedal for acceleration, cannot be provided to the driver while reducing undesired vehicle vibration caused by the torsion in the driving force transmission shaft.
Particularly in cases where the arts described in JP3750626B and JP5920147B are adopted, an engine torque is corrected to reduce the vehicle vibration even during acceleration. For this reason, it is difficult to provide a satisfactory response to the driver's acceleration request during the vehicle acceleration.